Not exactly sure how I came upon it tonight. I was searching "beehive construction". Anyway, it's a page on the North Dakota State University website. It is loaded with PDF files. Some - well, most are a "wee bit" dated. But, you never know when you may have to go back to depending on technology of days gone by, to survive. PAGE LINK A few of the files I happened to view at while browsing this page, and the dates they were drawn: Refrigerator - 1920 Water System To House (Windmill) - 1925 Water Well Pump Installation - 1964 I hope some of these benefit others here.